Synchronized expandable hinge assembly

ABSTRACT

A portable information handling system housing rotationally couples first and second housing portions with a hinge assembly that provides a variable distance between the housing portions, such as with first and second axles move together and apart or with a main bracket having telescoping members on opposing sides that provide rotation about a minor axis. Increased distance between the housing portions may accommodate a keyboard disposed between the housing portions or provide extra space if an object is placed between the housing portions so that a display integrated in the housing is not damaged.

CROSS REFERENCE TO RELATED APPLICATIONS

U.S. patent application Ser. No. 16/583,794, entitled “Synchronized DualShaft Expandable Hinge” by inventors Anthony J. Sanchez, John TrevorMorrison, and George Tzeng, filed on even date herewith, describesexemplary methods and systems and is incorporated by reference in itsentirety.

U.S. patent application Ser. No. 16/583,800, entitled “Synchronized DualShaft Expandable Hinge” by inventors James H. Hallar and John TrevorMorrison, filed on even date herewith, describes exemplary methods andsystems and is incorporated by reference in its entirety.

U.S. patent application Ser. No. 16/583,808, entitled “SynchronizedExpandable Dual Axle Hinge and Clutch” by inventors James H. Hallar andJohn Trevor Morrison, filed on even date herewith, describes exemplarymethods and systems and is incorporated by reference in its entirety.

U.S. patent application Ser. No. 16/583,816, entitled “Belt SynchronizedExpandable Dual Axle Hinge” by inventors James H. Hallar and John TrevorMorrison, filed on even date herewith, describes exemplary methods andsystems and is incorporated by reference in its entirety.

U.S. patent application Ser. No. 16/583,828, entitled “Bi-StableSynchronized Dual Axle Hinge” by inventors James H. Hallar and JohnTrevor Morrison, filed on even date herewith, describes exemplarymethods and systems and is incorporated by reference in its entirety.

U.S. patent application Ser. No. 16/583,835, entitled “SynchronizedSingle Axle Hinge” by inventors Jason S. Morrison and John TrevorMorrison, filed on even date herewith, describes exemplary methods andsystems and is incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates in general to the field of portableinformation handling systems, and more particularly to a portableinformation handling system synchronized dual shaft expandable hinge.

Description of the Related Art

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option available to users is information handling systems. Aninformation handling system generally processes, compiles, stores,and/or communicates information or data for business, personal, or otherpurposes thereby allowing users to take advantage of the value of theinformation. Because technology and information handling needs andrequirements vary between different users or applications, informationhandling systems may also vary regarding what information is handled,how the information is handled, how much information is processed,stored, or communicated, and how quickly and efficiently the informationmay be processed, stored, or communicated. The variations in informationhandling systems allow for information handling systems to be general orconfigured for a specific user or specific use such as financialtransaction processing, airline reservations, enterprise data storage,or global communications. In addition, information handling systems mayinclude a variety of hardware and software components that may beconfigured to process, store, and communicate information and mayinclude one or more computer systems, data storage systems, andnetworking systems.

Portable information handling systems integrate processing components, adisplay and a power source in a portable housing to support mobileoperations. Portable information handling systems allow end users tocarry a system between meetings, during travel, and between home andoffice locations so that an end user has access to processingcapabilities while mobile. Tablet configurations typically expose atouchscreen display on a planar housing that both outputs information asvisual images and accepts inputs as touches. Convertible configurationstypically include multiple separate housing portions that rotationallycouple to each other so that the system converts between closed and openpositions. For example, a main housing portion integrates processingcomponents and a keyboard and rotationally couples with a hinge assemblyto a lid housing portion that integrates a display. In a clamshellconfiguration, the lid housing portion rotates approximately ninetydegrees to a raised position above the main housing portion so that anend user can type inputs while viewing the display. After usage,convertible information handling systems rotate the lid housing portionover the main housing portion to protect the keyboard and display, thusreducing the system footprint for improved storage and mobility.

One disadvantage of integrating a keyboard in a portable informationhandling system housing is that only one-half of the upper surface areaof the housing includes a display to present visual images. Analternative approach is to have both upper surfaces of rotationallycoupled housing portions integrate a display so that an end user has alarger display area for viewing visual images. In some instances, aseparate liquid crystal display (LCD) panel is integrated in eachhousing portion. Alternatively, a flexible organic light emitting diode(OLED) display film may extend over both housing portions. Informationhandling systems that integrate a display over both rotationally coupledhousing portions typically support a clamshell configuration bypresenting a keyboard at one display and accepting keyed inputs astouches at the keyboard. Although such virtual keyboards provide aconvenient input device, end users typically prefer physical keyboardsthat have moving keys.

One solution available to end users is to interface with the informationhandling system through a peripheral keyboard, such as through awireless interface. Peripheral keyboards are available to support keyinputs to a portable information handling system that have a minimalistfootprint for improved mobility. For instance, a peripheral keyboardwith approximately the same width as the integrated display may restover the display while an end user types inputs. Such peripheralkeyboards typically have a minimal Z height and weight to provide readystorage and improved mobility. Often portable information handlingsystems have carrying cases that provide a storage pocket for theperipheral keyboards.

One difficulty that can arise with peripheral keyboards used at dualdisplay information handling systems is that end users will attempt toclose the housing portions over top of the keyboard. Portableinformation handling system hinge assemblies for dual display systemstend to have a minimal size so that the housing portions remain close toeach other and thus have less of a break between different viewingsurfaces on different housing portions. Further, convertible informationhandling system hinge assemblies tend to have dual axles synchronized bygears so that the housing portions do not interfere with each otherduring the transition between closed and tablet configurations. Often,hinge assembly gears have a minimal size and precise manufacture thatdoes not respond well to application of excessive force, such as canhappen if the housing portions are shut over top of an object like akeyboard. If a hinge assembly gear binds, the housing portions may failto rotate or damage may occur to the displays if an end user attempt torotate the housing portions introduces excessive torsional force. Inaddition to damage to the hinge assembly, closing housing portions overtop of an object may result in damage to the display due to the forceapplied by the object against the display.

SUMMARY OF THE INVENTION

Therefore, a need has arisen for a system and method which adaptsportable information handling system hinge assemblies to provide avariable distance between housing portions closed over an object.

A further need exists for a dual axle hinge assembly that synchronizeshousing portion rotation at varying distances between the dual axles.

A further need exists for a single axle hinge assembly that providesrotation between closed and tablet positions without interferencebetween the housing portions during rotation.

In accordance with the present invention, a system and method areprovided which substantially reduce the disadvantages and problemsassociated with previous methods and systems for rotationally couplinginformation handling system housing portions. A hinge assemblyrotationally couples the housing portions at variable distances for agiven orientation to provide clearance between the housing portions andto separate the housing portions if an object prevents rotation to adesired position, such as closure of the housing portions over akeyboard.

More specifically, a portable information handling system processesinformation with processing components disposed in a housing havingseparate housing portions rotationally coupled by a hinge assembly. Theinformation is presented as visual images at one or more displaysintegrated in the housing. The hinge assembly synchronously rotates thehousing portions to provide 360 degrees of rotation between closed andtablet positions. In one embodiment, synchronous rotation is provided bya dual axle hinge assembly having the dual axles interfaced to transferrotation between the axles. Transfer of rotation is provided between theaxles as the axles vary distance between each other. One example dualaxle embodiment couples the axles with a scissor assembly that expandsand contracts to adjust the distance between the axles. Mesh gearsinterface with each other at a fixed gear support to transfer rotationcommunicated with the axles by a translation axle interfaced through aset of universal joints. Another example dual axle embodimentcommunicates axle rotation through helical gears and an idler assemblyhaving helical and mesh gears so that the idler assembly supportsrotation transfer at variable axle distances. Yet another example dualaxle embodiment transfers axle rotation with bands that route rotationthrough translation pulleys at variable axle distances.

One example embodiment provides dual axle synchronized motion forhousing portions at multiple gear ratios so that the housing portionscan have a compressed or expanded relative position. A clutch engages toshift one of the dual axle positions relative to a gear assembly so thata desired gear ratio is engaged. In the example embodiment and similarembodiments, logic executing on a controller, such as firmware stored inflash memory and executed on an embedded controller, detects an objecton a display, such as keyboard, and adjusts the hinge assembly toprovide room for the object between the housing portions. As analternative to clutch selection of a gear ratio, the position of dualaxles may remain unchanged relative to each other but adjust relative tothe housing portion. For example, a breakaway bracket releases inresponse to a separating force at the hinge to increase the distancebetween the axle supported by the bracket and the housing portion, thusincreasing the distance between the housing portions.

Another example embodiment provides synchronous housing portion rotationand variable distances between housing portions with a single axis hingeassembly. A main bracket couples to one housing portion on a main axiswith rotationally coupled telescoping members extending from opposingends. First and second secondary brackets couple to the other housingportion at opposing ends of the main bracket so that pivoting of thetelescoping members at the main bracket and the secondary bracketsdefines a minor axis of rotation offset from the main axis. A camsurface at the secondary bracket interface with the telescoping memberand a linkage across the main bracket cooperate to synchronize motion ofthe housing portions. In addition to the synchronized motion thatresults from the minor axis shifting around the main axis, thetelescoping members provide extra extension to create space between thehousing portions if needed to close over top of an object, such as akeyboard.

The present invention provides a number of important technicaladvantages. One example of an important technical advantage is that aninformation handling system rotates housing portion in a synchronizedmanner with a variable distance provided between the housing portions toadapt to objects placed between the housing portions without damage tothe system. Variable distance between the housing portions is providedby a variety of embodiments including a dual axle hinge assembly thatchanges the distance between the axles, a dual axle hinge assembly thatbreaks away a bracket to change the distance between the housing and thehinge axles, a single axle hinge assembly that defines a minor axis withtelescoping members to vary distance between housing portions, and aclutch that selects different gear ratios to rotate the housingportions. By adapting housing portion spacing with a hinge assembly,objects disposed between the housing portions are less likely to causedamage to the system display and to the hinge assembly. An automatedresponse, such as based upon pressure applied towards separation of thehousing portions from each other, prevents damage in an object isinadvertently left between the housing portions. Further, flexibleresponse by a hinge assembly to unexpected forces provides a more robustsystem less sensitive to extreme operating conditions and externalstresses.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be better understood, and its numerousobjects, features and advantages made apparent to those skilled in theart by referencing the accompanying drawings. The use of the samereference number throughout the several figures designates a like orsimilar element.

FIG. 1 depicts an exploded perspective view of an information handlingsystem having an expandable hinge assembly configured to provide spaceto close rotationally coupled housing portions over a peripheralkeyboard;

FIGS. 2A and 2B depict a side view of an information handling systemhinge assembly in a compressed position having opposing displaysadjacent to each other and an expanded position having opposing displaysspread apart from each other;

FIG. 3 depicts a side perspective view of a hinge assembly having ascissors assembly to adjust a distance between parallel and laterallyaligned axles;

FIG. 4 depicts an exploded side perspective view of a gear scissorssupport with universal ball joints to translate rotational movementbetween hinge assembly axles;

FIG. 5 depicts a side perspective view of a biasing sleeve configured tointeract with an axle to restrict hinge expansion to predeterminedangular relationships;

FIG. 6 depicts a side perspective view of the hinge assembly disposed ina housing having slidingly engaged upper and lower portions;

FIGS. 7A and 7B depict a side view of a hinge assembly having a scissorsassembly that coordinates movement of parallel axles between expandedand compressed configurations;

FIG. 8 depicts a side perspective view of the hinge assembly havingcables routed through at the varied axle distances;

FIG. 9 depicts a side perspective view of a hinge assembly havinghelical gear synchronized variable distance axles driven by an idlerassembly biased to a compressed position;

FIG. 10 depicts an exploded side perspective view of the helical geardriven synchronized variable axle distance hinge assembly;

FIG. 11 depicts a side view of a hinge assembly in a compressed positionwith a cross sectional view indication;

FIG. 12 depicts a cross sectional view of a hinge assembly havinghelical and mesh gears engaged to transfer rotation between axles in acompressed position;

FIG. 13 depicts a side view of the hinge assembly in a compressedposition illustrating a drive carriage rotationally coupled to an idlersupport member;

FIG. 14 depicts a side view of a hinge assembly in an expanded positionwith idler assembly gear assemblies transferring rotation betweenparallel axles at an increased distance relative to the compressedposition;

FIG. 15 depicts a side view of an alternative embodiment hinge assemblyhaving axles biased to a compressed positions by a constant forcespring;

FIG. 16 depicts a sider perspective view of an alternative embodimenthinge assembly having a band cover disposed between upper and lowerhousing covers;

FIG. 17 depicts a side perspective view of a biased belt driven hingeassembly that synchronizes housing portion rotation at variable axledistances through translation pulleys;

FIG. 18 depicts a side cross sectional view of an example of rotationalmovement translation between hinge assembly axles;

FIG. 19 depicts an exploded view of a hinge assembly having biased beltdriven synchronized expanding axles;

FIG. 20 depicts an alternative single belt driven hinge assembly thatprovides synchronous rotation of axles at variable distances;

FIG. 21 depicts a side cross sectional view of the single belt drivenassembly illustrating belt flow across the pulleys;

FIG. 22 depicts a side perspective exploded view of a hinge assemblyhaving a biased idler mesh gear to expand and compress in support ofvertical axle movement;

FIGS. 23A and 23B depict a hinge assembly that adapts to multiple axledistances with a clutch selection of gear assemblies having differentgear ratios;

FIGS. 24A and 24B depict an example hinge assembly clutch actuation thatillustrates the relationship of the clutch axle position at actuationand before transition from the compressed position to the expandedposition;

FIGS. 25A and 25B depict an example hinge assembly clutch actuation thatillustrates the relationship of the clutch axle position after actuationand transition to the expanded position;

FIG. 26 depicts an exploded upper perspective view of one exampleembodiment of a clutch that changes gear ratios at a hinge assembly;

FIG. 27 depicts an upper perspective view of a portable informationhandling system in a flat tablet configuration having a single axlehinge assembly that adjusts housing portions to have variable distancebetween each other;

FIGS. 28A, 28B and 28C depict the portable information handling systemhaving the single axle hinge in a closed configuration with a spreadhousing position between the housing portions;

FIG. 29 depicts a rear perspective cutaway view of the informationhandling system adapting the hinge assembly to varying distances asneeded during closing of the housing portions;

FIG. 30 depicts a side view of the single axis hinge assembly having thesecondary brackets offset to a minor axis of rotation;

FIG. 31 depicts an upper perspective view of the single axis hingeassembly synchronized translation of telescoping member rotation;

FIGS. 32A, 32B, and 32C depict upper perspective views of the singleaxis hinge assembly secondary bracket synchronized translation ofrotation through the telescoping member;

FIG. 33 depicts an upper perspective view of an example of cable routingthrough the single axis hinge assembly;

FIG. 34 depicts a side perspective exploded view of a breakaway brackethinge assembly that adjusts housing portion spacing of an informationhandling system;

FIGS. 35A and 35B depict an upper perspective cutaway view of thebreakaway bracket hinge assembly holding information handling systemhousing portions in an adjacent position;

FIGS. 36A and 36B depict an upper perspective cutaway view of thebreakaway bracket hinge assembly supporting dual axle housing portionrotation;

FIGS. 37A and 37B depict a breakaway bracket hinge assembly rotationallycoupling information handling system housing portions about dual axlesin a flat tablet configuration prepared to close over a keyboard;

FIGS. 38A and 38B depict an upper perspective cutaway view of thebreakaway bracket hinge assembly closing over a keyboard with anexpanded configuration spacing between housing portions; and

FIGS. 39A, 39B and 39C depict alternative embodiments of breakawaybracket activation devices that adapt to variable distances betweeninformation handling system housing portions.

DETAILED DESCRIPTION

A portable information handling system housing rotationally coupleshousing portions with a hinge assembly that selectively varies thedistance between the housing portions, such as by expanding the hingeassembly to provide space for a keyboard disposed between the housingportions. For purposes of this disclosure, an information handlingsystem may include any instrumentality or aggregate of instrumentalitiesoperable to compute, classify, process, transmit, receive, retrieve,originate, switch, store, display, manifest, detect, record, reproduce,handle, or utilize any form of information, intelligence, or data forbusiness, scientific, control, or other purposes. For example, aninformation handling system may be a personal computer, a networkstorage device, or any other suitable device and may vary in size,shape, performance, functionality, and price. The information handlingsystem may include random access memory (RAM), one or more processingresources such as a central processing unit (CPU) or hardware orsoftware control logic, ROM, and/or other types of nonvolatile memory.Additional components of the information handling system may include oneor more disk drives, one or more network ports for communicating withexternal devices as well as various input and output (I/O) devices, suchas a keyboard, a mouse, and a video display. The information handlingsystem may also include one or more buses operable to transmitcommunications between the various hardware components.

Referring now to FIG. 1, an exploded perspective view depicts aninformation handling system 10 having an expandable hinge assembly 18configured to provide space to close rotationally coupled housingportions 14 over a peripheral keyboard 36. Information handling system10 has a portable configuration built in a portable housing 12 thatsupports mobile operations with integrated processing components,input/output devices and power supply. In the example embodiment,housing 12 has first and second housing portions 14 that each integratea display one on side, such as a liquid crystal display (LCD) panel oran organic light emitting diode (OLED) display panel. In alternativeembodiments, a single flexible OLED display film may extend across bothhousing portion 14 upper surfaces to fold at hinge assembly 18 whentransitioned to a closed position. Hinge assembly 18 includes pluralbrackets 20 that couple to each housing portion 14, such as with screwsor other coupling devices. As is described in greater depth below, hingeassembly 18 rotates housing portions 14 between a closed position havingdisplays 16 adjacent to each other to a variety of open positions, suchas a clamshell position having approximately 90 degrees of rotation, aflat tablet position having approximately 180 degrees of rotation, atent position having approximately 270 degrees of rotation and a tabletconvertible position having approximately 360 degrees of rotation.

In the example embodiment, information handling system 10 processingcomponents interface through a motherboard 22 to coordinate processingof information. For example, a central processing unit (CPU) 24 executesinstructions to processing information with the instructions andinformation stored in random access memory (RAM) 26. An embeddedcontroller 28 manages control of hardware components, such as power andthermal management, and of interactions with I/O devices, suchtouchscreens integrated with displays 16. A chipset 30 coordinatesoperation of CPU 24, such as by managing clock speed and memorytransactions. A graphics processor unit (GPU) 32 interfaces with CPU 24,such as through coordination by chipset 30, to generate pixel valuesthat define visual images for presentation at displays 16. A wirelessnetwork interface card (WNIC) 34 provides wireless communication, suchas through a wireless personal area network (WPAN) that interfaces withperipheral keyboard 36. In various embodiments, various types ofprocessing components may cooperate to process information in variousconfigurations of portable information handling systems. For instance,rather than a dual display 16 system as depicted by the exampleembodiment, a single display 16 in one housing portion 14 and anperipheral keyboard 36 in another housing portion 14 may be used. Hingeassembly 18 adapts a distance between housing portions 14 in the eventan object is closed between the housing portions that could damage adisplay 16. Various example embodiments of such hinge assemblies aredescribed below in greater detail.

Referring now to FIGS. 2A and 2B, a side view of information handlingsystem 10 depicts hinge assembly 18 in a compressed position havingopposing displays 16 adjacent to each other and an expanded positionhaving opposing displays spread apart from each other. FIG. 2Aillustrates the relative position of housing portions 14 at completionof rotating to a closed position about hinge assembly 18 to bringdisplays 16 adjacent to each other. As with conventional portableinformation handling systems, the adjacent position seeks to compresshousing portions 14 to close proximity so that the Z-height of thesystem is minimal for improved portability. FIG. 2B illustrates therelative position of opposing housing portions 14 where hinge assembly18 has an expanded configuration to provide a spaced position betweendisplays 16, such as with a peripheral keyboard 36 left in betweenhousing portions 14. In the example embodiment, hinge assembly 18defines a spaced position having at least the thickness of keyboard 36and transitions to the spaced position by compressing opposing displays16 around keyboard 36. For example, hinge assembly 18 includes a biasingdevice that biases it to a compressed configuration and that is overcomeat a predetermined force to transition to the expanded configuration.The compression force that overcomes biasing of hinge assembly 18 has athreshold set sufficiently small so as to avoid damage to displays 16.The amount of space provided by expanding of hinge assembly 18 may belimited to the thickness of peripheral keyboard 36 or may providegreater spacing to protect against other objects that may inadvertentlybe placed between housing portions 14. In one example embodiment,objects placed on a display are detected, such as by the touchscreen ofthe display, so that an actuator is used to transition hinge assembly 18to the expanded configuration.

Referring now to FIG. 3, a side perspective view depicts a hingeassembly 18 having a scissors assembly 38 to adjust a distance betweenparallel and laterally aligned axles 40. Hinge assembly 18 is in anexpanded configuration having an additional space provided betweenparallel axles 40 as reflected by the expanded cross members 42 ofscissor assembly 38. Each axle 40 terminates in a bracket 20 thatcouples to separate information handling system housings 14. Scissorsassembly 38 has first and second cross members 42 rotationally coupledat a central pivot location 44 and at opposing ends to axles 40 so thataxles 40 maintain a substantially parallel orientation during movementbetween the expanded and compressed positions. One end of each crossmember 42 couples to a biasing sleeve 46 inserted around an axle 40 toslide laterally as the distance between axles 40 adjusts. The oppositeends of each cross member 42 couples to a collar 48 having a fixedlocation laterally along axles 40. An extension 50 of collar 48 slideswithin a groove 52 to provide alignment of axles 40 in a fixed lateralposition while compensating for a changed vertical distance betweenaxles 40. Biasing sleeve 46 adapts to changes in the relative length ofscissors assembly 38 by sliding biasing sleeve 46 along each axle 40motivated by scissors assembly 38 cross members 42. A spacer 54 couplesto each axle 40 and defines a range of vertical motion towards thecompressed configuration. A biasing spring 56 is disposed betweenbiasing sleeve 46 and collar 48 to bias scissors assembly 38 towards acompressed position. An expanding force operating on hinge assembly 18,such as by an object placed between two housing portions coupled tobrackets 20 and rotated closed, overcomes the bias of biasing spring 56to slide biasing sleeve 46 towards collar 48. In one example embodiment,biasing spring 56 releases biasing sleeve 46 to slide along axle 40 if aforce separating axles 40 is within a threshold of a force associatedwith damage to a display closed over an object.

Rotational movement of axles 40 translates between axles 40 throughsynchronizing gears 58 held in proximity to each other during verticalmovement of axles 40 by a gear support 60. Gear support 60 is held in acentral position of axles 40 by a gear scissors support 62 having across member coupled to opposing sides of collar 48 to maintain thecentral position of gear support 60 as axles 40 move vertically. Eachaxle 40 has a torque generator 64 coupled proximate collar 48 togenerate torque that resists rotational movement and terminates at auniversal joint 66, each of which rotates with its respective axle 40.At the end of each universal joint 66, a translation axle 68 translatesrotation between each axle 40 and each synchronous gear 58. Universaljoints 66 adapt to variations in distances between axles 40 by adjustingthe angle of translation axle 68 to the relative fixed position ofsynchronous gears 58. Rotation within universal joints 66 of translationaxles 68 and rotation of gear scissors support 62 at collar 48 and gearsupport 60 cooperate to maintain engagement of synchronous gears 58.

Referring now to FIG. 4, an exploded side perspective view depicts agear scissors support universal ball joints to translate rotationalmovement between hinge assembly axles. Each translation axle 68terminates on both opposing ends with a round end 70 sized to snap intoa rounded receptacle 72 formed in both synchronizing gears 58 anduniversal joint 66. Round end 70 couples with round receptacle 72 tomaintain a fixed rotational relationship of universal joint 66 andsynchronous gear 58 through translational axle 68 while providingoff-axis rotation as the distance between axles 40 changes. Squarereceptacles 74 fit onto the ends of each axle 40 without a need foroff-axis rotation. In alternative embodiments, universal joint 66 couldhave a rounded coupling at axle 40 that provides off-axial rotationwhile translation axles 68 fixed co-axial with the opposite side ofuniversal joint 66. Various other off-axis translations of rotationbetween axles 40 and synchronous gears 58 may be used.

Referring now to FIG. 5, a side perspective view depicts a biasingsleeve 46 configured to interact with an axle 40 to restrict hingeexpansion to predetermined angular relationships. Biasing sleeve 46includes an extension 76 from an inner circumference that extends intoan axle guide 78 formed in axle 40. Extension 76 engages axle guide 78to define rotational angles at which sliding of biasing sleeve 46 isallowed along axle 40. If extension 76 interacts with axle guide 78 toprevent sliding of biasing sleeve 46, then axles 40 cannot movevertically with respect to each other. Preventing the expanding apart ofaxles 40 may be a desired behavior between 90 and 270 degrees of housingportion rotation since an object will not be captured between thehousing portions over that rotational range. Allowing expansion betweenzero and 90 degrees of rotation and between 270 and 360 degrees ofrotation helps to prevent damage caused by an object caught betweenclosing housing portions. In various embodiments, axle guide 78 mayprovide various amounts of rotation at varying housing orientations toachieve a desired degree of protection for the information handlingsystem.

Referring now to FIG. 6, a side perspective view depicts hinge assembly18 disposed in a housing 80 having slidingly engaged upper and lowerportions. During normal operations in a compressed configuration,brackets 20 synchronously rotate to separate housing portions. As aseparating force is applied at brackets 20 that overcomes biasing byhinge assembly 18 to the compressed position, housing 80 has twoseparate housing portions 82 that slide apart as the axles 40 of hingeassembly 18 increase their vertical distance between each other.

Referring now to FIGS. 7A and 7B, a side view of a hinge assembly 18depicts a scissors assembly 38 that coordinates movement of parallelaxles 40 between expanded and compressed configurations. FIG. 3A depictshinge assembly 18 in an expanded configuration having an additional 4.0mm of space provided between parallel axles 40 relative to thecompressed configuration depicted by FIG. 3B. Scissors assembly 38 firstand second cross members 42 rotationally couple at a central pivotlocation 44 and at opposing ends to axles 40 so that axles 40 maintain asubstantially parallel orientation during movement between the expandedand compressed positions. One end of each cross member 42 couples to abiasing sleeve 46 inserted around an axle 40 to slide laterally as thedistance between axles 40 adjusts. The opposite ends of each crossmember 42 couples to a collar 48 having a fixed location laterally alongaxles 40 to hold axles 40 in a fixed lateral orientation during relativevertical movement. Extension 50 slides within groove 52 to providealignment of axles 40 in the fixed lateral position while compensationfor a changed distance between axles 40 is provided by sliding ofbiasing sleeves 46 along each axle 40 motivated by scissors assembly 38cross members 42. Opposite collar 48 from scissor assembly 38, gearscissors support 62 extends and retracts gear support 60 so thatsynchronizing gears 58 remain engaged while translation axles 68 rotateoff axis from axles 40 to translate rotational movement between axles 40with synchronizing gears 58.

Comparing FIGS. 7A and 7B illustrates the interaction of hinge assembly18 components as axles 40 vary the distance between them by 4.0 mm. InFIG. 7A, scissors assembly 38 expands to separate axles 40 from eachother by 4.0 mm distance compared with the compressed configuration ofscissors assembly 38 in FIG. 7B. Scissors assembly 38 slides biasingsleeves 46 along axles 40 towards collar 48 in FIG. 7A and pushesbiasing sleeves 46 away from collar 48 in FIG. 7B. Similarly, gearscissors support 62 moves gear support 60 away from collar 48 withmovement from the expanded configuration of FIG. 7A to the compressedconfiguration of FIG. 7B so that the longer relative engagement oftranslation axles 68 are compensated for as the compressed positionaligns axles 40, translation axles 68 and synchronizing gears 58 in amore co-linear manner.

Referring now to FIG. 8, a side perspective view depicts hinge assembly18 having cables 84 routed through at the varied axle distances. Cable84 enters each side of hinges assembly 18 at a cable holder 86 andpasses across hinge assembly 18 with a U-shaped loop. The U-shape loopin cable 84 within hinge assembly 18 allows cable 84 to smoothly deflectas hinge assembly 18 expands and contracts. In part, cable managementmay take advantage of defined angles of rotation at which axles 40 arerestricted from varying the distance between each other.

Referring now to FIG. 9, a side perspective view depicts a hingeassembly 18 having helical gear 88 synchronized variable distance axles40 driven by an idler assembly 90 biased to a compressed position. Inthe example embodiment, each axle 40 has a helical gear 88 fixed on theouter surface and engaged with an idle assembly 90, which transfersrotation between axles 40 at variable distances. Idler assembly 90 hastwo separate idler gear assemblies coupled to each other by an idlersupport member 98. Each idler gear assembly has an idler helical gear 94fixed to an idler mesh gear 96. Each idler helical gear 94 engages withan axle helical gear 88 to transfer axle rotation to the idler mesh gear96. Both idler mesh gears 96 of idler assembly 90 are engaged at a fixeddistance to each other by idler support member 98. As the distancebetween axles 40 varies, idler assembly 90 changes it orientationbetween the parallel orientation shown by FIG. 9 in the compressedposition to a perpendicular orientation, such as is depicted in FIG. 14.A biasing spring 56 disposed on one axle 40 biases idler assembly 90towards a compressed position. A torque generator 64 generates torque tocontrol motion of axles 40.

Referring now to FIG. 10, an exploded side perspective view depicts thehelical gear driven synchronized variable axle distance hinge assembly18. A lower axle 40 inserts through a bottom opening of a bottom gearchassis 100 and an upper axle 40 inserts through a top opening of a topgear chassis 102. In addition, upper axle 40 inserts through a drivecarriage 104 that moves laterally along axle 40 in support of verticalaxle movement as described below. Idler assembly 90 resides withinbottom gear chassis 100 and top gear chassis 102 to maintainsynchronized axle rotation at variable axle distances. In the exampleembodiment, one end of idler support member 98 rotationally couples witha first idler pin 106 to bottom gear chassis 100 and rotationallycouples with a second idler pin 106 to drive carriage 104 within topgear chassis 102. In response to vertical expansion of axles 40 apartfrom each other, drive carriage 104 slides along the upper axle 40 torotate idler assembly 90 upwards from a parallel orientation of idlersupport member 98 to a perpendicular orientation. In the exampleembodiment, each axle 40 also passes through an opening of a housingcover portion 82 so that the gears are protected during movement with asliding vertical relationship of housing cover portions 82. Biasingspring 56 biases against drive carriage 104 to bias idler assembly 90towards a parallel orientation. Further, a magnet 108 attracts top gearchassis 102 to bias axles 40 toward the compressed position. Helicalgears 88 remain engaged with idler helical gears 94 as axle distancevaries while idler mesh gears 96 adjust their relative verticalpositions to transfer axle 40 rotational movement at varying axledistances.

Referring now to FIG. 11, a side view depicts hinge assembly 18 in acompressed position with a cross sectional view indication. In thedepicted compressed position, parallel axles 40 support informationhandling system housing portions disposed with opposing displays in anadjacent position, such as where no objects are disposed between thedisplays. Each axle 40 fixedly couples to a helical gear 88 for transferof rotational movement about the axle 40. Idler assembly 90 transfersrotational movement between helical gears 88 through first and secondgear assemblies that each fixedly couple an idler helical gear 94 to anidler mesh gear 96. Each idler helical gear 94 engages with a helicalgear 88 of fixedly coupled to an axle 40 so that the helical gears 94each rotate their fixedly coupled mesh gear 96. Idler support member 98holds mesh gears 96 in a spaced engaged relationship to transferrotation by idler helical gears 94. Biasing spring 56 biases againstrotation of idler support member 98 from the depicted orientation havingidlers support member 98 substantially parallel to axles 40.

Referring now to FIG. 12, a cross sectional view depicts hinge assembly18 having helical and mesh gears engaged to transfer rotation betweenaxles 40 in a compressed position. The cross sectional view, as takenfrom the cross sectional indication of FIG. 11, illustrates gearengagement to transfer rotation between axles 40. Helical gears 88coupled to axles 40 rotate with axles 40 and engage idler helical gears94 held in place by the idler support member. Idler helical gears 94 inturn rotate mesh gears 96 so that rotation of each axle 40 transfersthrough the two idler gear assemblies to each other.

Referring now to FIG. 13, a side view depicts hinge assembly 18 in acompressed position illustrating a drive carriage 104 rotationallycoupled to an idler support member 98. Drive carriage 104 rotationallycouples at one end of idler support member 98 with an idler pin 106 sothat a separating force operating to increase spacing between axles 40pulls drive carriage 104 along the upper axle 40 to compress biasingspring 56. Lateral motion of drive carriage 104 along axle 40 pullsidler support member 98 upwards from the depicted parallel orientationtowards a perpendicular orientation relative to axles 40 whilemaintaining engagement of helical gears 88 through idler helical gears94 and idler mesh gears 96. In the depicted compressed position, drivecarriage 104 is held in proximity with a magnet 108 to further biasaxles 40 towards remaining in the compressed position.

Referring now to FIG. 14, a side view depicts hinge assembly 18 in anexpanded position with idler assembly 90 gear assemblies transferringrotation between parallel axles 40 at an increased distance relative tothe compressed position. Drive carriage 104 has slid laterally along theupper axle 40 to compress biasing spring 56 and lift the side of idlersupport member 98 to which it rotationally couples. Idler assembly 90idler helical gear 94 is held engaged against the upper axle 40 helicalgear 88 by idler pin 106 passing through drive carriage 104 and throughthe rotational axis of the idler helical gear 94. Idler support member98 maintains engagement of mesh gears 96 so that the lower idler helicalgear 94 interfaces with the lower axle 40 helical gear 88 to transferrotation between axles 40 in the expanded configuration. Thus,synchronized axle 40 rotation is supported in the compressed andexpanded configurations and during movement along range between fullycompressed with idler support member 98 substantially parallel to axles40 to fully extended with idler support member 98 substantiallyperpendicular to axles 40.

Referring now to FIG. 15, a side view depicts an alternative embodimenthinge assembly 18 having axles biased to a compressed positions by aconstant force spring 109. Constant force spring 109 has a first endcoupled to a structure shared with bottom axle 40, such as bottom gearchassis 100, and an opposing end to upper axle 40 so that both axles 40rotate freely. Constant force spring 109 generates a constant biasingforce at both axles 40 towards a compressed position, which translatesthrough idler mesh gears 96 to rotate idler support member 98 to aparallel configuration. In various embodiments, biasing force generatedby constant force spring 109 may vary, such as by control provided froman embedded controller or other system management. For instance, if aninformation handling system detects a keyboard on a display, theembedded controller may command a reduced biasing force at constantforce spring 109 so that less stress is placed against the display inthe event the information handling system housing covers are rotated toa closed position over the keyboard.

Referring now to FIG. 16, a side perspective view depicts an alternativeembodiment hinge assembly 18 having a band cover 110 disposed betweenupper and lower housing cover portions 82. Band 110 protects themid-range of hinge assembly 18 while avoiding a sliding overlap ofhousing cover portions 82 to adapt as hinge 18 moves to the compressedposition. For instance, band 110 may have linkages to housing coverportions 82 that provide an impression of band 110 remaining stationaryduring hinge assembly 18 expansion and contraction.

Referring now to FIG. 17, a side perspective view depicts a biased beltdriven hinge assembly 18 that synchronizes housing portion rotation atvariable axle 40 distances through translation pulleys 114. Each axle 40inserts through a main axle pulley 112. Main axle pulleys 112 translaterotational movement through translation pulleys 114 so that the axles 40rotate in a synchronous manner. First and second main bands 116rotationally couple each main axle pulley 112 to a translation pulley114 and a translation band 118 rotationally couples the two translationpulleys 114. First and second axle supports 120 rotationally couple toeach main axle 40 to hold each translation pulley 114 in a fixedparallel relationship with its associated main axle pulley 112.Translation support members 122 rotationally couple to translationpulleys 114 to hold translation pulleys 114 in a fixed parallelrelationship while adjusting a vertical distance between axles 40 byadjusting the vertical relationship of translation pulleys 114. Biasingsprings 56 couple at each axle 40 to bias axle supports 120 andtranslation support members 122 towards a compressed position thatminimizes vertical distance between axles 40. A counter rotation drive124 interfaces at one axle 40 to adapt distance between axles 40 in theevent a separating force is applied to axles 40 while in a compressedposition so that counter rotation can, in effect, operate to separateaxles 40 from each other.

Referring now to FIG. 18, a side cross sectional view depicts an exampleof rotational movement translation between hinge assembly axles 40. Inthe example embodiment, each axle 40 fixedly couples to a main axlepulley 112 to co-rotate about an axis shared with axle supports 120.Main bands 116 translate rotation from each main axle pulley 112 to itstranslation pulley 114 rotationally coupled at the opposing end of eachaxle support 120. Translation pulleys 114 transfer rotation between eachother, as indicated by the arrows, with a translation band 118. Aseparation force applied at axles 40 to increase the distance betweenaxles 40 pulls translation support member 122 from a horizontalorientation between translation pulleys 114 towards a verticalorientation that maintains rotational motion transfer between axles 40.Axle supports 120 rotate about their respective axle 40 towards avertical orientation so that the length of translation support member122 extends between the ends of axle support 120 to increase thedistance between the axles 40. Housing cover portions 82 slide apart asthe distance between axles 40 increase and slide together when thedistance between the axles 40 decrease.

Referring now to FIG. 19, an exploded view depicts a hinge assembly 18having biased belt driven synchronized expanding axles. A top chassis102 has an opening to accept top axle 40, which passes through axlesupport 120. Biasing spring 56 operates against top chassis 102 to pressaxles 40 towards each other in the compressed position. Top chassis 102slidingly engages with bottom chassis 100 to adjust the distance betweenaxles 40. Bottom chassis 100 has a counter rotation drive 124 axle 126proceeding out an opening with main axle 40 coupled to the opposing sideof counter rotation drive 124 to transfer rotation. Counter rotationdrive 124 has first and second gears 128 that cooperate to rotate axle126 and first and second pulleys 130 interfaced through a belt 132 totransfer motion associated with axle 126. During normal operations,rotation passes from axle 126, through gears 128 and across a minor axleto pulleys 130 and belt 132 for transfer to axle 40. In a compressedposition of axles 40, rotational force applied to axle 126 translates toa counter rotation that drives axles 40 apart.

In the example embodiment, main axle pulleys 112 and translation pulleys114 have a smooth outer surface divided into three regions, eachassociated with the location of engagement by main bands 116 andtranslation bands 118. Main bands 116 and translation bands 118 are, forinstance, a resilient rubber material with a high friction to maintainconsistent rotational motion transfer. Biasing springs 56 work againstchassis 100 and 102 to drive axles 40 towards a compressed position. Aseparating force at axles 40 that overcomes the biasing to thecompressed position results in an increased distance between axles 40with an inward rotation of axle supports 120.

Referring now to FIG. 20, an alternative belt driven hinge assembly 18provides synchronous rotation of axles at variable distances. Mainpulleys 112 and translation pulleys 114 integrate grooves 134 that guidea single band 136 about their circumferences. Axle support 120 andtranslation support members 122 maintain spacing between main pulleys112 and translation pulleys 114 so that a separation force applied ataxles 40 provides an expanded position with rotation of translationsupport member 122 from a horizontal towards a vertical position. Aswith the multiple band embodiment described above, the housing aroundpulleys 112 and 114 slidingly expands and contracts with axle movement.Single band 136 has multiple wraps around each pulley to provideadequate tension for transfer of rotational movement between the axles40.

Referring now to FIG. 21, a side cross sectional view depicts the singlebelt driven hinge assembly 18 illustrating single band 136 flow acrossthe pulleys 112 and 114. In the example embodiment, single band 136 hasa relatively small diameter, such as a cable with a rubberized outersurface, which affixes at opposing ends in the main pulleys 112.Multiple windings around each of pulleys 112 and 114 adapt to verticalcompressing and spreading of axles 40 as axle supports 120 andtranslation support members move vertically relative to each other.

Referring now to FIG. 22, a side perspective exploded view depicts ahinge assembly having a biased idler mesh gear to expand and compress insupport of vertical axle movement. As with the biased band gear assemblydescribed above, axles 40 proceed through chassis 100 and 102 and coupleinternally through axle supports 120. Mesh axle gears 138 fixedly coupleto each axle 40 within the axle support 120 and are held engaged withidler gear 140 by axle support 120 coupling at its end to idler gear 140by idler pin 106. Idler support members 98 hold idler gears 140 engagedwith each other so that rotation at one of the mesh axle gears 138translates through idler gears 140 to the other mesh axle gear 138. Aseparating force pulling main axles 40 apart transfers through chassis100 and 102 to rotate idler support members 98 from a horizontal to avertical orientation with the fixed spatial relationship between meshaxle gears 138 and idler gears 140 is maintained by axle supports 120and idler support members 98. Biasing springs 56 operate against chassis100 and 102 to bias axles 40 towards a compressed position having idlersupport member 98 in a horizontal orientation. Housing cover portions 82slidingly engage to extend and compress with axles 40 as describe above.

Referring now to FIGS. 23A and 23B, a hinge assembly 18 adapts tomultiple axle 40 distances with a clutch 142 selection of clutch gearassembly 144 having compressed and expanded gear ratios 146 and 148. Inthe example embodiment, hinge assembly 18 has a compressed gear ratio146 that provides normal dual axle 40 motion to synchronously rotatehousing portions 14 from the closed position depicted by FIG. 23B for360 degrees to a tablet position. Compressed gear ratio 146 of clutchgear assembly 144 holds housing portions 14 to have displays 16 in anadjacent position without space between them that could accommodate akeyboard disposed between housing portions 14. When clutch 142 engagesthe expanded gear ratio 148, the effect is to expand housing portions 14apart from each other. Clutch 142 operates with a clutch actuator 150and clutch release spring 160 that cooperate to pull clutch lever 152between compressed and expanded positions. Clutch lever 152 moves aclutch fork 154 which extends or retracts axle 40 into and out of aclutch housing 156. An axle clutch adapter 158 aligns with clutchhousing guides 160 to ensure that the expanded gear ratio 148 andcompressed gear ratio 146 remain synchronized at desired housingpositions.

Referring now to FIGS. 24A and 24B, an example hinge assembly clutchactuation depicts the relationship of the clutch axle position atactuation and before transition from the compressed position to theexpanded position. Clutch lever 152 has actuated to push clutch fork 154towards clutch gear assembly 144 to push axle 40 out of clutch housing156, thus engaging expanded gear ratio 148 instead of compressed gearratio 146. FIG. 24B illustrates the position of housing portions 14before the engagement of expanded gear ratio 148 where hinge assembly 18holds housing portions 14 adjacent at the rotational axis. Clutch lever152 is, for instance, pulled between extended and compressed positionsby passing a current through a nickel titanium alloy spring to changephase. Alternatively, a solenoid, electromagnet or other actuator may beused. In one embodiment, clutch transition between compressed andexpanded positions may be commanded by firmware executing on an embeddedcontroller or other logic based upon detection of keyboard 36 on adisplay 16 and/or between housing portions 14. Alternatively, clutch 142may automatically release from the compressed position if apredetermined force is detected upon closing of housing portions 14.Note that clutch 142 has released axle 40 to select expanded gear ration148, however, clutch gear assembly 144 has not yet moved from compressedgear ratio 146 so that clutch gear assembly 144 remains alignedsubstantially in plane with housing portions 14.

Referring now to FIGS. 25A and 25B, an example hinge assembly 18 clutchactuation depicts the relationship of the clutch axle 40 position afteractuation and transition to the expanded position. Expanded hinge ratio148 adjusts the synchronous motion of axles 40 so that housing portions14 reach a parallel orientation in a spaced relationship rather thanwhen adjacent to each other. As illustrated by FIG. 25B, the expandedposition provides space between housing portions 14 to hold keyboard 36.Clutch gear assembly 144 in the expanded gear ratio 148 shifts to a morevertical disposition when closed over keyboard 36. If keyboard 36 wereremoved and housing portions 14 pushed together, clutch gear assembly144 would shift to the more horizontal disposition show by FIG. 24A. Inthe depicted example position, axle clutch adapter 158 is out ofalignment with clutch housing guides 160 as the axle 40 has not fullyrotated due to the different gear ratio that is engaged. Beveled edgesformed between clutch housing guides 160 and axle clutch adapter 158 maybe used to help guide axle 40 back into position for the compressed gearratio 146. In the example embodiment, clutch housing guide 160 may forcealignment in a fully closed, fully open or flat tablet housing positionif a clutch actuation is attempted.

Referring now to FIG. 26, an exploded upper perspective view depicts oneexample embodiment of a clutch that changes gear ratios at a hingeassembly. Axle 40 inserts into clutch housing 156 and fixedly couples toaxle clutch adapter 158, which interacts with clutch fork 154. Top plate162 couples over top of bracket 20 to hold clutch fork 154 in place.Actuator and release springs 150 and 161 couple to clutch lever 152 andbracket 20 to selectively move lever 152 between the compressed gearratio and expanded gear ratio positions. In the example embodiment, axle40 slides laterally in response to clutch fork 154 movement of axleclutch adapter 158 so that a gear fixed on axle 40 moves from engagementwith a compressed gear ratio to an expanded gear ratio that interfacesthe parallel axle 40. In the example embodiment, transition between gearratios generally is limited to housing portion 14 configurations wherethe gears match positions between the gear ratios, such as at zero, 180and 360 degrees of rotation. In alternative embodiments, clutch 142 mayadjust other aspects of the gear interactions that allow changes atother housing orientations, such as by having clutch 142 change theidler gear size between two main axle gears that remain stationary.

Referring now to FIG. 27, an upper perspective view depicts a portableinformation handling system 10 in a flat tablet configuration having asingle axis hinge assembly 18 that adjusts housing portions 14 to havevariable distance between each other. Hinge assembly 18 couples to onehousing portion 14 with a main bracket 166 and to the other housingportion 14 with first and second secondary brackets 168 coupled atopposing ends of main bracket 166. First and second telescoping members170 rotationally couple main bracket 166 at opposing ends to secondarybrackets 168. A main axis 172 is defined along the length of mainbracket 166 and, in the flat tablet configuration as depicted, atelescoping axis 174 and minor axis 176 are aligned collinear with mainaxis 172. Power and information pass between housing portions 14 througha cable 84 that extends through an opening form through secondarybracket 168 and telescoping member 170. In the flat tablet configurationas depicted, single axis hinge assembly 18 occupies the volume of aconventional single axis hinge but includes three rotational joints andone sliding joint that adjust housing portion 14 position to supportrotation in a manner similar to that of a dual axis hinge. Morespecifically, as housing portions rotate from the flat configuration toa closed configuration, telescoping axis 174 extends secondary brackets168 to rotate about minor axis 176 displaced off main axis 172.

Referring now to FIGS. 28A, 28B and 28C, portable information handlingsystem 10 is depicted having the single axle hinge assembly 18 in aclosed configuration with a spread housing position between the housingportions 14. Main axis 172 is defined at the housing portion 14 havingmain bracket 166 while telescoping members 170 extend up at an angle tosecondary brackets 168, which rotate about minor axis 176. In theexample embodiment, hinge assembly 18 separates housing portions 14 byan amount sufficient to accept a keyboard between housing portions 14.The additional space illustrates how single axis hinge assembly 18provides spare room as needed between housing portions 14; however, asis set forth in greater detail below, biasing integrated in hingeassembly 18 works to bring housing portions 14 adjacent to each other.From the side view depicted by FIG. 28C, the effective change indistance between the main axis and minor axis illustrates the singleaxis approach adapting to motion of housing portions 14 through 360degrees of rotation.

Referring now to FIG. 29, a rear perspective cutaway view of informationhandling system 10 depicts adaptation of hinge assembly 18 to varyingdistances as needed during closing of housing portions 14. Bothtelescoping members 170 have synchronously rotated relative to mainbracket 166 to raise secondary brackets 168 for alignment with minoraxis 176. The relative vertical movement provided by telescoping members170 adapts the position of minor axis 176 relative to main axis 172 sothat housing portions 14 rotate without interfering with each other. Asthe distance between main axis 172 and minor axis 176 changes, thelength of telescoping member 170 adapts, allowing secondary bracket 168to pivot at the end about minor axis 176.

Referring now to FIG. 30, a side view depicts single axis hinge assembly18 having the secondary brackets 168 offset to a minor axis 176 ofrotation. Telescoping member 170 rotationally couples at opposing endsto main bracket 166 and secondary bracket 168 at pivots 186 so thatsecondary bracket 168 is held parallel and off-axis with main bracket166. Telescoping member 170 has a first element 178 that sliding insertsinto a second element 180 to change its length as the off-axis distancebetween main axis 172 and minor axis 176 changes. Motion of telescopingmembers 170 at pivot 186 to main bracket 166 is synchronized by a pushrod and biasing device, while motion about pivot 186 at secondarybracket 168 is synchronized by a cam. The push rod synchronizationpasses across opposing sides of main bracket 166 through opposinglinkages. A first linkage 182 couples to an upper side of a firsttelescoping member 170 with a first push rod 192 that works against asecond linkage 184 coupled to a lower side of main bracket 166 and asecond push rod 192. Similarly, linkages 188 and 190 work in opposingdirections through third and fourth push rods 192. As a result, if oneof the telescoping members 170 rotates at a pivot 186 to main bracket166, then the other telescoping member 170 is motivated to rotate aboutits pivot 186 in a synchronous manner.

Referring now to FIG. 31, an upper perspective view of the single axishinge assembly 18 depicts synchronized translation of telescoping memberrotation. A biasing spring 56 is disposed around each push rod 192 tobias telescoping members 170 towards a collinear orientation with mainbracket 166. Linkages 182 and 184 couple with a first pin 194 thatslides laterally in main bracket 166. Similarly, linkages 188 and 190couple with a second pin 194 that slides laterally in main bracket 166.Rotational movement about pivots 186 thus work against a bias towards acollinear orientation and transfer through the linkages across mainbracket 166 to the telescoping member at the opposing end.

Referring now to FIGS. 32A, 32B, and 32C, upper perspective views depictthe single axis hinge assembly 18 secondary bracket 168 synchronizedtranslation of rotation through the telescoping member 170. FIG. 32Adepicts secondary bracket 168 rotating about an axis defined by rotationat pivot 186, which aligns with minor axis 176. To achieve alignment ofsecondary bracket 168 with minor axis 176, a cam surface 198, shown byFIG. 32B, works against push rods 196 extending out of telescopingmember 170. As rotation occurs about main axis 172, cam surface 198moves push rods 196 to force rotation of the minor axis 176. In oneexample embodiment, cam surface 198 has a flat portion, such as between90 and 270 degrees of housing portion rotation, which does not move pushrods 196 so that housing portions 14 remain in close proximity throughthat rotation range. During housing portion 14 rotation of 0-90 and270-360 degrees of rotation, cam surface 198 works against push rods 196to force minor axis 176 to rotate as needed to allow housing portions 14room to move without interference. In addition, cam surface 198 allows alift off so that additional minor axis 176 rotation can accommodate anincreased spacing between housing portions 14, such as to allow closingof housing portions 14 over a keyboard. Cam surface 198 forces rotationof minor axis 176 to minimize wear between housing portions 14, whichwould otherwise work against each other, and to allow a sharper housingedge at hinge assembly 18 that reduces spacing between displays ofopposing housing portions with the housing in a flat tabletconfiguration.

Referring now to FIG. 33, an upper perspective view depicts an exampleof cable 84 routing through the single axis hinge assembly 18. In theexample embodiment, a biasing device 204, such as a spring, maintainstension on cable 84 passing through a central opening of telescopingmember 170 and secondary bracket 168. As telescoping member 170 pivotsto move the minor axis about which secondary bracket 168 rotates,biasing device 204 maintains sufficient tension on cable 84 to preventbunching and to encourage cable 84 to slide within the opening.

Referring now to FIG. 34, a side perspective exploded view depicts abreakaway bracket 206 hinge assembly 18 that adjusts housing portion 14spacing of an information handling system 10. In the example embodiment,breakaway bracket 206 offers a traditional 360 degree hinge assemblythat supports a convertible housing configuration and that separates toconvert between adjacent and separated spacing between housing portions14 if an object is placed between the housing portions. Breakawaybracket 206 captures an axle plate 212 between an upper hinge bracket208 and a bottom hinge bracket 216, such as with screws that couple tohousing portion 14. Axle plate 212 extends an axle 40 from one end thatcouples to a hinge knuckle 218 and a hinge barrel 214 that defines arotational axis within bottom bracket 216 and upper bracket 208. In acompressed configuration that holds housing portions 14 and integrateddisplays 16 adjacent to each other, a bi-stable magnet 210 attracts axleplate 212 against upper hinge bracket 208 with a pivot about arotational axis defined at hinge barrel 214. Bottom bracket 216 biasesaxle plate 212 to remain rotated upwards and against upper bracket 208.However, with a sufficient separating force applied from axle 40, axleplate 212 breaks away from upper bracket 208 and towards bottom hingebracket 216 by rotating about an axis defined at hinge barrel 214.Movement by axle plate 212 towards bottom hinge bracket 216 createsadditional space at hinge knuckle 218 to separate the housing portionsapart from each other. Once the separation force is removed, magnet 210biases axle plate 212 towards upper hinge bracket 208 to return hingeassembly 18 from the spaced configuration to the adjacent configuration.In one example embodiment, magnet 210 is an electro permanent magnetthat may selectively increase or reduce magnetic attractive force, suchas with a control signal provided from an embedded controller or othersystem management processor.

Referring now to FIGS. 35A and 35B, an upper perspective cutaway viewdepicts the breakaway bracket 206 hinge assembly 18 holding informationhandling system housing portions 14 in an adjacent position. In theexample embodiment, hinge barrel 214 couples to first and second axlesextending from first and second housing portions 14 and may includesynchronizing gears or other synchronizing devices that cooperate torotate housing portions. A breakaway bracket 206 may be used tointerface both housing portions 14 to hinge knuckle 218 or just onebreakaway bracket 206 may be used at one housing portion 14. In theexample embodiment, first and second actuator springs 220 engage with aretainer 222 to selectively release retainer 222 and set axle plate 212free to rotate. For instance, actuator springs 220 are nickel titaniumalloy material that pull retainer 222 arms away from axle plate 212 whena current is applied to change the material phase. Retainer 222 hasbeveled edges that bias over axle plate 212 so that sufficient forcepulling axle plate 212 against retainer 222 pushes the retainer arms outand away from axle plate 212 so it can rotate within upper and lowerbrackets 208 and 216. In the example embodiment, retainer 222 is formedas part of bottom hinge bracket 216 with a resilient plastic materialthat biases the retaining arms inward and over axle plate 212. Bevelededges are formed on both sides of retainer 222 to aid in passage of axleplate 212 between the adjacent/compressed position and thespaced/expanded position.

Referring now to FIGS. 36A and 36B, an upper perspective cutaway viewdepicts the breakaway bracket 206 hinge assembly 18 supporting dual axlehousing portion 14 rotation. With axle plate 212 biased against upperhinge bracket 208, such as under the influence of magnet 210 andretainer 222, hinge assembly 18 rotates housing portions 14 in aconventional manner, such as synchronously with a gear mechanismdisposed in hinge knuckle 218.

Referring now to FIGS. 37A and 37B, a breakaway bracket 206 hingeassembly 18 rotationally couples information handling system 10 housingportions 14 about dual axles 40 in a flat tablet configuration preparedto close over a keyboard 36. In one embodiment, housing portions 14close over top of keyboard 36 to generate a separating force at axles 40that releases axle plate 212 to provide an expanded configuration withroom between displays 16 for keyboard 36. In an alternative embodiment,breakaway bracket 206 is released based upon detection of keyboard 36 sothat a closing force is not applied against displays 16.

Referring now to FIGS. 38A and 38B, an upper perspective cutaway viewdepicts breakaway bracket 206 hinge assembly 18 closing over a keyboard36 with an expanded configuration spacing between housing portions 14.Hinge assembly 18 expands to provide space for keyboard 36 betweenhousing portions 14. The expanded space is created by release of axleplate 212 from retainer 222 to rotate within upper and lower brackets208 and 216 so that axle 40 moves away from its housing portion 14. Oncekeyboard 36 is removed from between the housing portions 14, acompressing force against housing portions 14 biases retainer 222outward and away from axle plate 212 so that axle plate 212 may returnto the compressed position against upper bracket 208.

Referring now to FIGS. 39A, 39B and 39C, alternative embodiments aredepicted of breakaway bracket 206 activation devices that adapt tovariable distances between information handling system housing portions.FIG. 39A depicts beveled edges 224 at the overlap of retainer 222 armsand axle plate 212. Beveling of the edges at the upper and lowersurfaces of retainer 222 beveled edge 224 aids transition of axle plate212 between its compressed and expanded positions. Actuation springs 220aid the transition between compressed and expanded configurations bypulling outward on retainer 222 when a housing proximity configurationchange is desired, such as when a keyboard is detected between orremoved from between housing portions 14. FIG. 39B depicts analternative embodiment of breakaway bracket 206 with actuation springs220 disposed over top of axle plate 212 to bias axle plate 212 to thecompressed position. In one embodiment, actuation springs 220 simplyapply a constant bias against axle plate 212 towards the compressedposition that is overcome if sufficient separating force is applied athousing portions 14. In an alternative embodiment, nickel titanium alloysprings may be used to adjust axle plate 212 position, such as with aflow of current that changes the spring tension. FIG. 39C depicts yetanother alternative embodiment having a balanced conical spring 226biasing axle plate 212 to the expanded position against a bi-stablemagnet 210, such as electro permanent magnet, biasing axle plate 212 tocompressed position. The magnetic attraction of electro permanent magnet210 may be switched between high and low states by logic executing on aembedded controller based upon operating conditions at informationhandling system 10.

Although the present invention has been described in detail, it shouldbe understood that various changes, substitutions and alterations can bemade hereto without departing from the spirit and scope of the inventionas defined by the appended claims.

What is claimed is:
 1. An information handling system comprising: ahousing having first and second housing portions; a processor disposedin the housing and operable to execute instructions to processinformation; a memory disposed in the housing and interfaced with theprocessor, the memory operable to store the instructions andinformation; a display disposed in the housing and interfaced with theprocessor, the display operable to present the information as visualimages; and a hinge assembly rotationally coupling the first and secondhousing portions to rotate between open closed positions, the hingeassembly varying the distance between the first and second housingportions in the closed position in response to one or more predeterminedconditions.
 2. The information handling system of claim 1 furthercomprising: a peripheral keyboard separate from the housing and having athickness; wherein the hinge assembly varies the distance between thefirst and second housing portions between an adjacent position of thefirst and second housing portions and the keyboard thickness.
 3. Theinformation handling system of claim 1 further comprising: a biasingdevice biasing the hinge assembly to varying the distance to an adjacentposition; wherein the display has a pressure constraint associated withdamage to the display and the biasing device increases the distancebetween the housing portions in response to movement of the housingportions to a closed position over an object that generates a forceagainst the display within a predetermined threshold of the pressureconstraint.
 4. The information handling system of claim 3 wherein thedisplay comprises a display viewing area that extends across both thefirst and second housing portions.
 5. The information handling system ofclaim 1 wherein the hinge assembly further comprises first and secondaxles held in a parallel disposition at the varied distances.
 6. Theinformation handling system of claim 5 further comprising a scissorsassembly having first and second cross members rotationally coupled tothe first and second axles to maintain the first and second axles in theparallel disposition at the varied distances.
 7. The informationhandling system of claim 5 further comprising first and second transferpulleys disposed between the first and second axles and cooperating totransfer rotation between the first and second axles in the paralleldisposition at the varied distances.
 8. The information handling systemof claim 1 wherein the hinge assembly further comprises: a single mainbracket coupled to a central location of the first housing portion:first and second secondary brackets coupled to opposing off centerlocations of the second housing portion; and first and secondtelescoping members rotationally coupling the single main bracket to thefirst and second secondary brackets, the first and second telescopingmembers adjusting between the varied distances.
 9. The informationhandling system of claim 8 further comprising a biasing device disposedon the single main bracket to bias the first and second telescopingmembers co-axial to the single main bracket.
 10. A method for rotatinginformation handling system housing portions about a hinge assembly, themethod comprising: rotationally coupling first and second housingportions with the hinge assembly; disposing an object on a displayintegrated in the first housing portion; rotating the first and secondhousing portions towards a closed position over the object; andexpanding the first and second housing portions apart from each otherwith the hinge assembly in response to pressure by the first and secondhousing portions against the object.
 11. The method of claim 10 furthercomprising: synchronizing motion of first and second housing portionswith the hinge assembly; biasing first and second axles of the hingeassembly towards each other; and overcoming the biasing to separate thefirst and second axles from each other to perform the expanding.
 12. Themethod of claim 11 wherein the synchronizing further comprises: engaginga first gear associated with the first axle and a second gear associatedwith the second axle at a central location; and translating motionbetween the first and second gears and the first and second axlesthrough first and second shafts interfaced by first and second universaljoints.
 13. The method of claim 12 wherein the expanding furthercomprises: coupling the first and second axles with a scissors assembly;and maintaining lateral alignment of the first and second axles with anextension associated with the first axle engaging a slot associated withthe second axle.
 14. The method of claim 11 wherein the synchronizingfurther comprises: rotationally coupling first and second transferpulleys with a transfer belt; rotationally coupling the first axle withthe first transfer pulley with a first belt; and rotationally couplingthe second axle with the second transfer pulley with a second belt. 15.The method of claim 14 wherein the restricting further comprisesmaintaining the translation of rotation between the first and secondaxles during the expanding by adjusting an orientation of the first andsecond transfer pulleys.
 16. A method for rotating information handlingsystem housing having first and second housing portions, the methodcomprising: rotationally coupling the first and second housing portionsabout a hinge assembly; and varying the distance between the first andsecond housing portions at the hinge assembly in response to apredetermined condition.
 17. The hinge of claim 16 wherein thepredetermined condition comprises a keyboard placed on a displayintegrated in the housing, the method further comprising: selectivelyactuating a clutch that adjusts one axle of the hinge assembly from afirst position to a second position; engaging a first gear assembly atthe first position having a first gear ratio; and engaging a second gearassembly at the second position having a second gear ratio.
 18. Thehinge of claim 16 wherein the rotationally coupling further comprises:coupling a first bracket at a central location of the first housingportion; coupling second and third brackets at offset locations of thesecond housing portion aligned at opposing sides of the first bracket;and interfacing the second and third brackets to the first bracketthrough first and second telescoping members having a variable length tovary the distance between the first and second housing portions.
 19. Thehinge of claim 18 further comprising biasing the first and secondtelescoping members to align co-linear with the first bracket.
 20. Thehinge of claim 19 further comprising: interfacing a first cam betweenthe first telescoping member and the third bracket; interfacing a secondcam between the second telescoping member and the second bracket; andtranslating rotation of the second bracket through the secondtelescoping member and through the biasing to rotate to the thirdbracket with interaction by the first telescoping member.